Cobble relief mechanism for rolling mill

ABSTRACT

A cobble relief mechanism for a rolling mill of a continuous metal casting and rolling system wherein the accumulation of rod within the mill housing is relieved by opening a portion of the housing and allowing the rod to play out of the opening. The housing is opened in response to the buildup of the rod within the housing, and when the rod is allowed to escape from the confines of the housing the hazard of damage to the rolling mill components is reduced and the entangled rod is played out beyond the housing until the operation of the rolling mill is terminated.

United States Patent West et al.

[4 1 June 27, 1972 [54] COBBLE RELIEF MECHANISM FOR ROLLING MILL [72] Inventors: David H. West; Kenneth R. Stone, both of Carrollton, Ga.

[73] Assignee: Southwire Company, Carrollton, Ga.

[22] Filed: May 18, 1970 [2]] App]. No.: 38,393

[56] References Cited UNITED STATES PATENTS Nieman ..72/234 2,573,353 l 0/l95l FOREIGN PATENTS OR APPLICATIONS 4,624 9/1882 Great Britain ..72/250 Primary Examiner-Charles W. Lanham Assistant Examiner-R. M. Rogers Attorney-Jones 8: Thomas 57 ABSTRACT A cobble relief mechanism for a rolling mill of a continuous metal casting and rolling system wherein the accumulation of rod within the mill housing is relieved by opening a portion of the housing and allowing the rod to play out of the opening. The housing is opened in response to the buildup of the rod within the housing, and when the rod is allowed to escape from the confines of the housing the hazard of damage to the rolling mill components is reduced and the entangled rod is played out beyond the housing until the operation of the rolling mill is terminated.

6 Claims, 4 Drawing Figures PATENTEDJUNZY m2 3.672.199

sum 1 or 2 INVENTORS 2 DAVID H4 WEST I H- KENNETH R STONE aad'hmi wrw ATTORNEYS ll COBBLE RELIEF MECHANISM FOR ROLLING MILL BACKGROUND OF THE INVENTION In a continuous metal casting system for forming rod wherein molten metal, such as molten copper or aluminum, is continuously poured into a casting machine, extracted from the casting machine in solid form and passed through a rolling mill where it is elongated and reduced in diameter and subsequently formed into a coil, it is usually difficult to terminate the continuous operation of the system on short notice, as when some malfunction of the system occurs. For instance, when a cobble occurs in the rod formed from the cast bar at a location in the systembetween the last roll stand of the rolling mill and the coiled rod, the rodusually will continue to pass from the last roll stand for a short time interval before the operation of the rolling mill can be terminated. During this time interval the cobble, which may have occurred in the coiling mechanism or in the housing of the rolling mill, is likely to cause the movement of the rod from the rolling mill housing to terminate while the rod will continue to pass through roll stands of the rolling mill. The rolling mill will tend to push the rod from the last roll stand, and since the rod is relatively flexible and tends to bend freely the rod tends to bend and fold before it passes from the rolling mill housing. A single bend or fold of the rod in the housing will cause the rod to play out from the last roll stand within the housing of the rolling mill, so that the rod tends to accumulate within the rolling mill housing before the operation of the rolling mill is terminated. The result is that the roll stands, spray nozzles, guide hardware and other parts in the housing are subject to being damaged by the rod playing out within the housing, and the accumulation of a mass of rod is diflicult to remove from the housing and from around the equipment in the housing.

SUMMARY OF THE INVENTION Briefly described, the present invention comprises a cobble relief mechanism for a rolling mill that functions to relieve the buildup of rod within the rolling mill housing due to the malfunction of a component of the system downstream from the last roll stand of the rolling mill. The rolling millhousing is equipped with a relatively large door opening at its exit end and a relief door normally closes the opening and defines a relatively small rod exit opening. Ifany rod should accumulate within the housing adjacent the exit of the housing,.it is likely that the rod will exert a force against the relief door and urge the relief door to its opened position. When the relief door is opened, the rod will tend to play out the opening instead of tending to accumulate within the housing of the rolling mill.

Thus, it is an object of this invention to provide a cobble relief mechanism for a rolling mill that reduces the hazard of damaging the components of the rolling mill that might occur if the rod is allowed to accumulate within the rolling mill hous- Another object of this invention is to provide a means of reducing the hazard of damaging the components of a rolling mill while allowing the rolling mill to continue its operation in a continuous casting system when a cobble has occurred in the system downstream from the last roll stand of the rolling mill.

Other objects, features, and advantages of the present invention will become apparent upon reading the following specification, when taken in conjunction with the accompanying drawing.

B IEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic side elevational view of a continuous casting, rolling and coiling system.

FIGS. 2, 3 and 4 are progressive side elevational views of the cobble relief mechanism of a rolling mill, showing the relief door closed (FIG. 2).showing a bend occurring in the rod (FIG. 3), and showing the relief door opening in response to the accumulation of the rod within the mill housing (FIG. 4).

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in more detail to the drawing, in which like numerals indicate like parts throughout the several views, FIG. 1 discloses a continuous casting, rolling and coiling system 10 that comprises a casting machine 11, a rolling mill 12 and coiling mechanism 13. Molten metal is poured in the arcuate mold 15 formed by a peripheral groove in casting wheel 16 and continuous band 17, and the molten metal is solidified with a liquid cooling system. The cast bar 18 is extracted from the mold and guided to rolling mill 12. A plurality of roll stands 19 are located in alignment with each other within a housing 20, and each roll stand 19 tends to elongate the bar 18 and reduce the bar in cross sectional area so that the bar emerges from the last roll stand 19 as rod 21. The rod is passed from housing 20 through a tube 22to pinch rolls 24, through coiling mechanism 13, where it is arranged in a coil 25. Pinch rolls 24 are driven so as to pull the rod up the tube 22 and urge it down through the tube of coiling mechanism 13. The rod 21 emerging from the rolling mill is relatively flexible, and pinch rolls 24 function to place enough tension in rod 21 to keep it from bending. Housing 20 substantially encloses the rolling mill and maintains a substantially inert atmosphere with a substantial amount of atomized soluble oil solution about the metal being worked in the mill.

While the system is constructed so as to prevent the likelihood of cobbles developing in the rod-or any other malfunctioning of the system, there are occasions when the system malfunctions and fails to deliver rod to the coil 25, as

when the rod accumulates in the rolling mill housing. When such a malfunction occurs, the mill operator usually severs the bar 18 extending from casting machine 11 to the rolling mill l2 and temrinates the operation of the rolling mill as soon as practical. The rod accumulated in the rolling mill housing is removed and the operation of the mill is continued as soon as practical, preferably before the metal has cooled, to remove the metal from the roll stands. The metal from the casting machine is again processed through the rolling mill to restart the continuous system.

As is illustrated in FIGS. 2,3 and 4, the exit end 26 of housing 20 of the rolling mill 12 comprises means for opening the housing in the form of relief door 28 which is a substantially upright door tapered at its edges into abutment with the end 29 of housing 20. Door 28 defines rod exit opening 30 which is in alignment with the normal rod path through the roll stands of the mill, and an air injector noule 31 is inserted through rod exit opening 30. Nozzle 31 defines a series of aligned internal axial bores which include small bore 32a at the inner end of the nozzle, larger counter bore 32b intermediate the ends of the nozfle, and threaded bore 32c at the outer end of the nonle. Small bore 32a is outwardly tapered at 34 at the inner end of the nozzle. Annular internal sloping surface 32d extends between large counter bore 32b and small bore 32a, and transverse bore 35 extends through the side of noule 31 and intersects large counter bore 32b. Externally threaded cylindrical nozzle insert 33 includes an inwardly sloping annular surface 33A and insert 33 is threaded into threaded bore 32a so that sloping surfaces 33a and 32d are closely spaced to form an annular converging channel. Central bore 33b of insert 33 is aligned with small bore 32a and taper 34 is arranged to receive and guide the lead end of rod 21 from housing 20, through small bore 324 and central bore 33b, and then to guide tube 22 leading from housing 20 to the coiling mechanism. Thus, once rod 21 enters the nozzle it tends to continue on into and through guide tube 22 toward coiling mechanism 13. Transverse bore 35 provides a connection for a flexible gas line so that a flow of gas through bore 35 into large bore 32b creates an annular air stream or air wipe" on the rod passing through nozzle 31 for air wiping the soluble oil solution from the rod as the rod emerges from the mill housmg.

As is best illustrated in FIG. 4, relief door 28 is hingedly connected to housing 20 by a plurality of overlapping protrusions 36 and 38 connected to door 28 and housing 20, respectively, and by hinge pin 39 extending through aligned openings in the protrusions. The hinge mechanism 37 is located at the lower portion of relief door 28 below and in front of its center of gravity so that the relief door tends to pivot downwardly away from housing 20 as illustrated in FIG. 4, to completely open the housing when allowed to move toward its opened position.

Yieldable retaining means 40 is mounted on housing 20 and tends to maintain relief door 28 in its closed position, as illustrated in FIG. 2. Yieldable retaining means 40 comprises a pair of upwardly extending latching lugs 41 mounted on top of relief door 28 with sloped latch faces 42, and a latch mechanism 44 mounted on housing 20 that includes upright supports 45,T-shaped latch arm 46, and latch nob 48. Spring housing 49 is maintained in an upright attitude above latch arm 46 by upright supports 45 and confines compression spring 50. Bearing yoke 51 protrudes from an opening 52 in the bottom wall 54,0fspringhusing 49 and its upper end is retained with the spring housing by enlarged flange 55 while the arms of its yoke at its lower end straddle latch arm 46. A threaded opening 56 is defined in the other end of spring housing 49 and threaded regulating screw 58 extends therethrough and its enlarged flange 59 compresses compression spring 50. When regulating screw 58 is rotated, the compression of spring 50 is altered, which alters the force with which latch nob 48 is urged into engagement with latch faces 42 of lugs 41.

For the purpose of this disclosure, latch arm 46 is illustrated as being a single T-shaped bar having its cross bar 60 pivotally received in aligned openings of spaced upright supports 45 and its'base bar 61 extending beneath bearing yoke 51,-and latch nob 48 is of spherical shape and rigidly mounted on the end of base bar 61. When relief door 28 is closed, latch nob 48 will be urged down the slope of latch face 42 by spring biased yoke 51, which tends to maintain the relief door in its closed position; however, the sloping surface of latch face 42 is disposed at an angle so that when enough force in the direction of movement of rod 21 is applied to relief door 28, latch nob 48 will ride up the slope of latch faces 42 and the door will be allowed to open.

Once a fold occurs in the rod and the rod continues to be processed through the rolling mill, the rod will tend to accumulate within the housing, as illustrated in FIG. 3. As the rod is urged against the relief door 28, a force is applied to the relief door which tends to pivot the relief door toward its opened position shown in FIG. 4. Once the yieldable retaining means 40 is overcome by the force of the rod being applied against the relief door, the relief door will tend to open to its wide open position since the center of gravity of the relief door is above and behind hinge pin 39. This causes the exit end of housing to be completely open, and the rod passing through the rolling mill will be allowed to play out of the opened exit end of the rolling mill where it can be severed and easily removed. When the rod has been cleared from the vicinity of the exit end of the housing and the continuous system is ready to be started again, relief door 28 is merely slammed shut and it will tend to remain in this closed condition by yieldable retaining means 40.

Regulating screw 58 can be rotated to vary the compression of spring 50, the force with which latch nob 48 is urged against latch faces 42, and the force required to open relief door 28. This feature is desirable since the mechanism is usable with rods of different hardness, such as aluminum alloy rod or copper alloy rod. Yieldable retaining means 40 would be adjusted so as to require less opening force when being used with the softer rod.

While this invention has been described in detail with particular reference to preferred embodiments thereof, it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinbefore and as defined in the appended claims.

We claim:

1. In a rolling mill for rolling cast bar into rod comprising a housing and a plurality of aligned roll stands positioned in said housing for working the of a metal from bar into rod, the combination wherewith a rod exit door substantially closing one end of said housing and defining an opening for the passage therethrough of the rod from the roll stands, said door positioned in a generally upright attitude when in its closed position and pivotable about a generally horizontal axis below its center of gravity in a direction away from said housing so that the weight of said door when in its opened position tends to maintain said door in its opened position, and yieldable retaining means for maintaining said door in its closed position until a predetermined force is applied to said'door.

2. In a rolling mill for rolling cast bar into rod comprising a housing and a plurality of aligned roll stands positioned in said housing for working the cast metal from bar into rod, the combination therewith of a rod exit door substantially closing one end of said housing and defining an opening for the passage therethrough of the rod from the roll stands, and yieldable retaining means for maintaining said door in its closed position until a predetermined force is applied to said door, said yieldable retaining means comprising a latch assembly including a latch member normally connected between said door and said housing, and spring means yieldably urging said latch member into connection between said door and said housing.

3. In a rolling mill for rolling cast bar into rod comprising a housing and a plurality of aligned roll stands positioned in said housing for working the cast metal from bar into rod, the combination therewith of a rod exit door substantially closing one end of said housing and defining an opening for the passage therethrough of the rod from the roll stands, said door including a latch protrusion, and retaining means comprising a latch arm pivotally connected at one of its ends to said housing and having its other end movable into engagement with said protrusion when said door is in its closed position and a yieldable spring member urging said latch arm into engagement with said protrusion, whereby said door is maintained in its closed position until a predetermined force is applied to said door.

4. In a rolling mill for continuously rolling cast bar into rod comprising a plurality of aligned roll stands and a substantially closed housing disposed about said roll stands for maintaining an inert atmosphere about said roll stands, whereby cast bar is received through one end of the housing, worked into rod by the roll stands and discharged through the exit end of the housing, the improvement therein of said housing defining an opening at its exit end, a door hingedly connected to said housing and normally closing said opening, a rod exit opening defined in said door for the passage therethrough of rod from the roll stands, and yieldable retaining means for maintaining said door in its closed position.

5. In a rolling mill for forming cast bar into rod and comprising a plurality of roll stands situated within a substantially closed housing for receiving cast bar through one end of said housing, continuously working the cast bar into rod and passing the rod through the exit end of said housing while maintaining a substantially inert atmosphere in said housing, the improvement therein of means for opening said housing in response to the accumulation of rod in said housing.

6. The invention of claim 5 and wherein said means for opening said housing comprises a door member normally maintained in its closed position and yieldable under a predetermined force to move to its fully opened position.

* t t a: t 

1. In a rolling mill for rolling cast bar into rod comprising a housing and a plurality of aligned roll stands positioned in said housing for working the of a metal from bar into rod, the combination wherewith a rod exit door substantially closing one end of said housing and defining an opening for the passage therethrough of the rod from the roll stands, said door positioned in a generally upright attitude when in its closed position and pivotable about a generally horizontal axis below its center of gravity in a direction away from said housing so that the weight of said door when in its opened position tends to maintain said door in its opened position, and yieldable retaining means for maintaining said door in its closed position until a predetermined force is applied to said door.
 2. In a rolling mill for rolling cast bar into rod comprising a housing and a plurality of aligned roll stands positioned in said housing for working the cast metal from bar into rod, the combination therewith of a rod exit door substantially closing one end of said housing and defining an opening for the passage therethrough of the rod from the roll stands, and yieldable retaining means for maintaining said door in its closed position until a predetermined force is applied to said door, said yieldable retaining means comprising a latch assembly including a latch member normally connected between said door and said housing, and spring means yieldably urging said latch member into connection between said door and said housing.
 3. In a rolling mill for rolling cast bar into rod comprising a housing and a plurality of aligned roll stands positioned in said housing for working the cast metal from bar into rod, the combination therewith of a rod exit door substantially closing one end of said housing and defining an opening for the passage therethrough of the rod from the roll stands, said door including a latch protrusion, and retaining means comprising a latch arm pivotally connected at one of its ends to said housing and having its other end movable into engagement with said protrusion when said door is in its closed position and a yieldable spring member urging said latch arm into engagement with said protrusion, whereby said door is maintained in its closed position until a predetermined force is applied to said door.
 4. In a rolling mill for continuously rolling cast bar into rod comprising a plurality of aligned roll stands and a substaNtially closed housing disposed about said roll stands for maintaining an inert atmosphere about said roll stands, whereby cast bar is received through one end of the housing, worked into rod by the roll stands and discharged through the exit end of the housing, the improvement therein of said housing defining an opening at its exit end, a door hingedly connected to said housing and normally closing said opening, a rod exit opening defined in said door for the passage therethrough of rod from the roll stands, and yieldable retaining means for maintaining said door in its closed position.
 5. In a rolling mill for forming cast bar into rod and comprising a plurality of roll stands situated within a substantially closed housing for receiving cast bar through one end of said housing, continuously working the cast bar into rod and passing the rod through the exit end of said housing while maintaining a substantially inert atmosphere in said housing, the improvement therein of means for opening said housing in response to the accumulation of rod in said housing.
 6. The invention of claim 5 and wherein said means for opening said housing comprises a door member normally maintained in its closed position and yieldable under a predetermined force to move to its fully opened position. 